American Museum Novitates

AMERICAN MUSEUM NOVITATES Number 3791, 66 pp. December 11, 2013 The Neotropical goblin spiders of the new genus Varioonops (Araneae, Oonopidae) ANGELO BOLZERN1 AND NORMAN I. PLATNICK1 ABSTRACT A new genus, Varioonops, is established for a group of species characterized by sexual dimorphism in abdomen morphology (with a dorsal scutum present in males but not females), male palps with a separate cymbium and bulb, and a patterned abdomen. The closest relatives of the new genus appear to be three similar, but as yet undescribed, Neotropical genera that share those characters, but the members of Varioonops are united by a putative synapomorphy that does not seem to occur in those undescribed groups: a granulated sternum. Attention is drawn to the cymbial cone, a structure (possibly a receptor) found near the tip of the cymbium in Varioonops, members of the Orchestininae, and at least some soft-bodied members of the Oonopinae. A total of 23 new species are described: V. cafista (the type species), V. velsala, V. montesta, V. spatharum, V. poas, V. varablanca, V. tortuguero, V. veragua, V. heredia, and V. girven from Costa Rica, V. ramila and V. sansidro from Costa Rica and Panama, V. funator and V. cerrado from Panama, V. edvardi and V. sinesama from Colombia, and V. yacambu, V. trujillo, V. pittieri, V. chordio, V. parlata, V. potaguo, and V. grancho from Venezuela. INTRODUCTION Through focused investigations of the spider family Oonopidae by the many participants in the goblin spider Planetary Biodiversity Inventory (PBI) project, several new genera and numerous new species have recently been described from the Neotropics. The northern Neo- tropics clearly constitute one of the hotspots of oonopid diversity, and most of the ground- dwelling species found there are microdistributed (i.e., are short-range endemics). Multiple 1 Division of Invertebrate Zoology, American Museum of Natural History. Copyright © American Museum of Natural History 2013 ISSN 0003-0082 2 American Museum Novitates NO. 3791 taxa, including even congeneric species, can often be found at a single site (Platnick and Dupérré, 2012), and the taxa placed here as members of the new genus Varioonops fit that pattern well. Of the 23 species treated below, found from Costa Rica to Venezuela, only four have been collected in more than two provinces. Multiple species of Varioonops have been found sympatrically at several localities; in most cases, the sympatric species belong to different species groups within the genus, but there is one exception. Two members of the tortuguero group, the new species V. ramila and V. veragua, have both been taken in the Veragua Rainforest at Los Gigantea in Limón, Costa Rica. Recent considerations of oonopid monophyly and interrelationships (Burger and Michalik, 2010; Platnick et al., 2012a) have resulted in the recognition of three subfamilies of goblin spiders, the Orchestininae, Sulsulinae, and Oonopinae. Based on the 3-3-2-2 tarsal organ receptor pattern (figs. 23–27), the lack of a heavily sclerotized sperm duct in the male palp (fig. 129), and the clumped eye arrangement (fig. 123), Varioonops belongs to the Oonopinae. Basal interrelationships within that huge subfamily remain poorly resolved, but one large group of genera, the gamasomorphines, are united by the putatively synapomorphic presence of a sperm pore on the epigastric scutum, far in advance of the epigastric furrow (Platnick et al., 2012a). That character is present in Varioonops. Most gamasomorphines also differ from the soft-bodied, non-gamasomorphine members of the Oonopinae in having lost an oblique, unsclerotized strip on the ventral surface of the basal segment of the anterior lateral spinnerets. The presence of that strip may be a synapomorphy of the entire superfamily Dysderoidea, but if so it has apparently been lost in all gamasomorphines other than Niarchos Platnick and Dupérré (see Gris- mado et al., in press); that strip is not found in the members of Varioonops. Although most gamasomorphines are hard bodied, with dorsal abdominal scuta present in adults of both sexes (although not in juveniles), the members of Varioonops are sexually dimorphic in that respect; males have a dorsal scutum on their patterned abdomen, but females do not (figs. 126, 137). This kind of sexual dimorphism has been reported in two groups of gamasomorphines. It is found in some members of the Dysderina complex (Plat- nick and Dupérré, 2011a, 2011b), and in all members of the Scaphiella complex (Platnick and Dupérré, 2009b, 2010a, 2011b, 2011c; Bonaldo et al., in press), and even in one genus of the related family Orsolobidae (Ott et al., 2013). However, Varioonops does not appear to be a member of either of those gamasomorphine complexes. The carapace shape, sternum shape, and leg spination suggest a closer relationship to the Dysderina complex, whereas the patterned abdomen is shared only with Pescennina Simon, a member of the Scaphiella complex (Platnick and Dupérré, 2011c). The members of both the Dysderina and Scaphiella complexes, however, all share an apomorphic feature of palpal morphology, the fusion of the palpal bulb with the cymbium. This feature has seemingly been acquired independently in some soft-bodied oonopines (Platnick and Berniker, 2013a, 2013b), but it does not occur in Varioonops. However, there are three other new Neotropical groups that are currently being described (Bolzern, in prep.; R. Ott, in litt.) whose members share at least the following characters with those of Varioonops: sexually dimorphic scuta (with females lacking dorsal abdominal scuta), 2013 BOLZERN AND PLATNICK: VARIOONOPS 3 a patterned abdomen, and a separate palpal cymbium and bulb. Thus, these groups together seem to constitute a third complex of sexually dimorphic Neotropical gamasomorphines. Within this complex, the members of Varioonops share two features also found in one of the undescribed genera that is likely to represent their sister group: a uniquely broad, triangular projection, bearing distally flattened setae, on the anterior portion of the male endites (figs. 7, 67–69) and a cluster of distally filiform glands situated at the base of the anterior genitalic process of females (figs. 44, 103, 157, 305, 472, 488). The species assigned here to Varioonops, however, all have a distinctly granulated sternum (figs. 4, 34, 64, 94, 378, 415, 462, 484) that appears to be unique to, and synapomorphic for, this group alone. While studying the male palps of Varioonops with scanning electron microscopy, we noted a peculiar structure near the tip of the cymbium (figs. 9, 70, 285, 363, 411, 458). It was detected in almost all the species, but on some specimens, in some positions, it can be fully obscured by the surrounding setae. This cymbial cone is situated on the dorsoretrolateral side of the cymbial tip. It may be a receptor, or a secretory structure, as there is often an opening visible at the tip. In previously published illustrations, we have detected the cymbial cone only in two African species of Orchestina Simon described by Henrard and Jocqué (2012: figs. 165, 166, 252, 253), but it is also apparent in images of an as yet undescribed South American species of Orchestina and members of two undescribed groups, as well as possibly in members of the soft-bodied oonopine genusNeotrops Grismado and Ramírez (2013). Given this relatively widespread distribution within the family, the cymbial cone is unlikely to be a synapomorphy of an oonopid subgroup, but the presence or absence of the character needs to be documented in other oonopid genera, especially those of the subfamily Sulsulinae, as well as in the other families of dysderoids. Among other unusual characters of Varioonops are the “false claws,” paired setae situated at the tips of tarsi III and IV that have a heavily sclerotized, enlarged, claw-shaped tip (figs. 21, 54, 448). Similarly modified setae have been found in several other groups, including some rather distantly related genera (Grismado et al., 2011; Ubick and Griswold, 2011; Platnick et al., 2012b; Bonaldo et al., in press). Also notable is a peculiarly short, modified seta situated distolaterally on metatarsi I–III (figs. 56, 88, 117). The position of these setae suggests that they may be involved in proprioception; differently shaped, modified setae can be found in the same position on members of other genera, including Orchestina (see Henrard and Jocqué, 2012: figs. 559, 560), Melchisedec Fannes (2010: figs. 42, 43), and Escaphiella Platnick and Dupérré, (2009b: fig. 42), but setae with this particular shape have been detected to date only in Vari- oonops and a closely related, undescribed group of species. So far as we have been able to determine, no oonopids previously described from the areas occupied by Varioonops appear to belong to the genus; apparently members of the group were never found by Arthur Chickering during his extensive fieldwork in Panama, and no specimens are known from the areas in southern Panama where most of his collections were made. Some informal species groups can be recognized, based primarily on the shape of the male embolus and conductor, but we are able to assign only 14 of the species to such groups; the groups are reflected in the key to species provided below. 4 American Museum Novitates NO. 3791 The cafista group (containing V. cafista and V. velsala) and the montesta group (containing V. montesta, V. poas, and V. spatharum) are known only from Costa Rica. The tortuguero group (containing V. ramila, V. tortuguero, V. varablanca, and V. veragua) and the sansidro group (containing V. heredia and V. sansidro) are also primarily Costa Rican, but each contain one species that extends into northern Panama. The yacambu group (containing V. pittieri, V. trujillo, and V. yacambu) is endemic to Venezuela. The members of these groups are united by the following details: the cafista group by the evenly curved embolus with a distinct plate-shaped tip in combination with a distinct opening on the conductor (figs.

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